[media] Replace MessageLoopProxy usage with ThreadTaskRunnerHandle

media/base/fake_text_track_stream.cc

Index: media/base/fake_text_track_stream.cc
diff --git a/media/base/fake_text_track_stream.cc b/media/base/fake_text_track_stream.cc
index 183e61ef2caf14ef7ce5e0dcd6ff8e74b6db7cea..214eec435bbcf8a5c20d91a86c50f374f19d992b 100644
--- a/media/base/fake_text_track_stream.cc
+++ b/media/base/fake_text_track_stream.cc
@@ -6,13 +6,15 @@
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
+#include "base/single_thread_task_runner.h"
+#include "base/thread_task_runner_handle.h"
 #include "media/base/decoder_buffer.h"
 #include "media/filters/webvtt_util.h"
 
 namespace media {
 
 FakeTextTrackStream::FakeTextTrackStream()
-    : task_runner_(base::MessageLoopProxy::current()),
+    : task_runner_(base::ThreadTaskRunnerHandle::Get()),
       stopping_(false) {
 }